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Observations and Reduction

Blue compact galaxies HS 1013+3809 (KUG 1013+381) and HS 1442+4250 (UGC 9497) were selected as candidates to emission-line galaxies on Hamburg Quasar Survey objective prism photoplates (Hagen et al. 1995). The galaxy HS 1442+4250 was already known from Popescu et al. (1996) as emission-line galaxy (ELG), but no classification and details of spectra were presented. For the galaxy HS 1013+3809 there were no spectral infromation in literature. Short exposure time follow-up spectroscopy at 6m telescope of SAO RAS on April 4 and 6, 1998 of these objects have shown quite strong emission line of [OIII] $\lambda$4363Å, what indicated high temperature T_e and possible low metallicity. Their higher S/N spectra were obtained on April 4, 5 and 6, 1998.

The spectrograph SP-124 in the Nasmyth-1 focus of the 6-m telescope with Schmidt-Cassegren camera and Photometrix CCD PM1024 ( $24\times24$$\mu$m pixel size) are used for these observations. The spatial scale along the slit is equal 0.4 $^{\prime\prime}$/pixel, the slit length is about 40 $^{\prime\prime}$, and the slit width of 2 $^{\prime\prime}$ is used. Grating with 600 grooves/mm is used, resulting in spectral resolution of approximately 7 Å (FWHM). Long-slit spectra in the ranges 3700-6100 (for HS 1013+3809 and HS 1442+4250) and 5000-7400 Å (HS 1442+4250) are obtained. The total exposure time for HS 1013+3809 was broken up on 2$\times$600 sec. For HS 1442+4250, the total exposure time was broken up on 3$\times$600 sec in blue, and 2$\times$420 sec -- in red. The seeing was 2.2 during of the observations.

The spectra were centered on the brightest central knot for HS 1013+3809 and SW knot in the elongated body of HS 1442+4250 (see DSS images of both galaxies in Figure 1). Series of bias images were obtained twice -- in the beginning and at the end of every night. Dark current and flat field were accumulated at the end of each night. Two standard stars from the list of spectrophotometric standards (Massey & Strobel, 1988) (mostly Feige 34 and HZ 44) were observed during every night. He-Ne-Ar lamp was used for wavelength calibration.

All observations are conducted under the software package NICE in MIDAS, described by Kniazev & Shergin (1995).

The raw spectroscopic data was reduced using the contexts CCDRED and LONG from the MIDAS software package. The reduction of the originally two-dimensional CCD data included the standard steps such as: bias and dark subtraction, flat-fielding, cosmic-ray removal. After wavelength mapping the subsequent night sky background subtraction was performed. Then the correction for atmospheric extinction and flux calibration were applied. For the flux calibration we used the mean response curve obtained from the observations of standard stars. 1-D spectra were extracted by adding several consecutive CCD rows centered on the object intensity peak along the slit.